Cooling module and a method of cooling an electronic circuit module using the cooling module

ABSTRACT

Example implementations relate to a cooling module, and a method of cooling an electronic circuit module. The cooling module includes first and second cooling components fluidically connected to each other. The first cooling component includes a first fluid channel having supply, return, and body sections, and a second fluid channel. The second cooling component includes an intermediate fluid channel. The body section is bifurcated into first and second body sections, and the first and second body sections are further merged into a third body section. The supply section is connected to the first and second body sections. The return section is connected to the third body section and the intermediate fluid channel via an inlet fluid-flow path established between the first and second cooling components. The second fluid channel is connected to the intermediate fluid channel via an outlet fluid-flow path established between the first and second cooling components.

CROSS REFERENCE

This application is related to a co-pending U.S. application titled“cooling module and a method of assembling the cooling module to anelectronic circuit module” filed on “Dec. 3, 2021” (U.S. ApplicationSerial Number XX/XXX,XXX), which has Invention Reference Number“90962589”, and is assigned to Hewlett Packard Enterprise DevelopmentLP.

BACKGROUND

An electronic system generally include one or more circuit assemblies,each having at least one electronic circuit module. Typically, anelectronic circuit module includes a circuit board and chipsets (e.g.,one or more electronic chips) disposed on the circuit board. Theseelectronic chips may generate waste-heat during their operation. If thewaste-heat is not dissipated from the electronic circuit module, thewaste-heat may exceed thermal specifications of the electronic chips,thus resulting in degraded performance, reliability, and life expectancyof the electronic circuit module having such electronic chips, and insome cases the failure of the circuit assembly having such electroniccircuit module. In order to minimize such adverse effects of thewaste-heat, the electronic system may include a thermal managementsystem for circulating a fluid (e.g., a cool fluid) to a cooling moduleof the circuit assembly to draw the waste-heat away from the electronicchips of the electronic circuit module.

BRIEF DESCRIPTION OF THE DRAWINGS

Various examples will be described below with reference to the followingfigures.

FIG. 1A illustrates an exploded perspective view of a circuit assemblyaccording to an example implementation of the present disclosure.

FIG. 1B illustrates an assembled perspective view of the circuitassembly of FIG. 1A according to an example implementation of thepresent disclosure.

FIG. 1C illustrates a cross sectional view of a first connector of apair of first fluid connectors having an O-ring, movably connected toanother first connector of a pair of second fluid connectors of FIGS.1A-1B according to an example implementation of the present disclosure.

FIG. 1D illustrates a cross sectional view of a first connector of apair of first fluid connectors having an O-ring, movably connected toanother first connector of a pair of second fluid connectors of FIGS.1A-1B according to another example implementation of the presentdisclosure.

FIG. 2A illustrates an exploded perspective view of a frame of thecircuit assembly of FIGS. 1A-1B according to an example implementationof the present disclosure.

FIG. 2B illustrates a perspective view of an electronic circuit moduleof the circuit assembly of FIGS. 1A-1B according to an exampleimplementation of the present disclosure.

FIG. 2C illustrates a cross sectional view of the electronic circuitassembly taken along line 1-1′ of FIG. 2B according to an exampleimplementation of the present disclosure.

FIG. 2D illustrates an exploded perspective top view of a cooling moduleof the circuit assembly of FIGS. 1A-1B according to an exampleimplementation of the present disclosure.

FIG. 2E illustrates an exploded perspective bottom view of a coolingmodule of the circuit assembly of FIGS. 1A-1B according to an exampleimplementation of the present disclosure.

FIG. 2F illustrates a perspective view of a spring loaded fastener of acooling module in the circuit assembly of FIGS. 1A-1B according to anexample implementation of the present disclosure.

FIG. 2G illustrates a perspective view of a captive fastener of thecooling module in the circuit assembly of FIGS. 1A-1B according to anexample implementation of the present disclosure.

FIG. 3 illustrates a perspective view of a portion of a first coolingcomponent and a captive fastener of FIGS. 1A-1B and FIG. 2G according toan example implementation of the present disclosure.

FIG. 4 illustrates a flowchart depicting a method of assembling acooling module according to an example implementation of the presentdisclosure

FIG. 5A illustrates a cross sectional top view of the circuit assemblytaken along line 2-2′ of FIG. 1B according to an example implementationof the present disclosure.

FIG. 5B illustrates a cross sectional top view of a cooling module ofFIGS. 1A-1B having a first cooling component and a second coolingcomponent according to an example implementation of the presentdisclosure.

FIG. 6 illustrates a flowchart depicting a method of drawing heat awayfrom an electronic circuit module by a cooling module according to anexample implementation of the present disclosure.

FIG. 7 illustrates a cross sectional view of a first connector of a pairof first fluid connectors movably connected to another first connectorof a pair of second fluid connectors according to another exampleimplementation of the present disclosure.

DETAILED DESCRIPTION

The following detailed description refers to the accompanying drawings.Wherever possible, the same reference numbers are used in the drawingsand the following description to refer to the same or similar parts. Itis to be expressly understood, however, that the drawings are for thepurpose of illustration and description only. While several examples aredescribed in this document, modifications, adaptations, and otherimplementations are possible. Accordingly, the following detaileddescription does not limit the disclosed examples. Instead, the properscope of the disclosed examples may be defined by the appended claims.

The terminology used herein is for the purpose of describing exampleembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. The term“plurality,” as used herein, is defined as two, or more than two. Theterm “another,” as used herein, is defined as at least a second or more.The term “coupled,” as used herein, is defined as connected, whetherdirectly without any intervening elements or indirectly with at leastone intervening element, unless otherwise indicated. Two elements may becoupled mechanically, electrically, or communicatively linked through acommunication channel, pathway, network, or system. The term “and/or” asused herein refers to and encompasses any and all possible combinationsof one or more of the associated listed items. It will also beunderstood that, although the terms first, second, third, etc. may beused herein to describe various elements, these elements should not belimited by these terms, as these terms are only used to distinguish oneelement from another unless stated otherwise or the context indicatesotherwise. As used herein, the term “includes” means includes but notlimited to, the term “including” means including but not limited to. Theterm “based on” means based at least in part on.

As used herein, the term “fluid connector” may refer to a type of amechanical coupler, which movably connects to another mechanical couplerso as to fluidically connect at least two fluid chambers to one another.As used herein the term “movably connected” or “movable connection” mayrefer to a non-rigid fluid connection formed between two fluidconnectors, where one of the fluid connectors may move 3-dimensionallyrelative to the other fluid connector, while maintaining a leak-prooffluid-flow path therebetween. As used herein the term “tool-less” designmay refer to a type of design incorporated in the fluid connectors thatenables the fluid connectors to be movably connected to one anotherwithout the need for any tools, to complete the assembly of coolingcomponents. As used herein the term “cooling component” may refer to atype of a thermal conductive component, which includes an internalchannel (or microchannel) through which a cool fluid is directed toabsorb a waste-heat transferred to the cooling component by a waste-heatproducing component, for example, one or more electronic chipsetsdisposed on a circuit board. For example, the cooling component may alsobe referred to as a cold plate. The term “fluid” may refer to a liquidmedium or a gaseous medium of the coolant or combinations thereof.Further, the term “plugging-in” may refer to connecting the fluidconnectors (e.g., a fluid bore or a fluid piston) to each other by wayof pushing or inserting one of the fluid bore or the fluid piston intothe other one of the fluid bore or the fluid piston. Similarly, the term“plugging-out” may refer to disconnecting the fluid connectors from eachother by way of pulling or extracting one of the fluid bore or the fluidpiston from the other one of the fluid bore or the fluid piston.Further, as used herein, the term “thermal interface” may refer tosurfaces of two components, which are directly in contact with eachother or indirectly in contact with each other through a thermalinterface material (TIM) to promote the transfer of the waste-heat fromone component to the other component. As used herein, the term “height”may refer to a tallness of an electronic chip from a bottom surface to atop surface of the electronic chip or from the bottom surface of thecircuit board to the top surface of the electronic chip. As used hereinthe term “flatness” may refer to an even surface (or a level surface ora uniform surface) of an electronic chip or a co-planarity between twoelectronic chips (for example, between the top surfaces) minimizingraised areas or indentations. For example, the electronic chip may havethe even top surface, when it has uniform height.

It may be noted herein: an object, device, or assembly (which mayinclude multiple distinct bodies that are thermally coupled, and mayinclude multiple different materials), is “thermally conductive” betweentwo thermal interfaces if any one of the following is true: (i) a heattransfer coefficient between the thermal interfaces is above 5 W/m²K atany temperature between 0° C. and 100° C., (ii) the object includes amaterial that has a thermal conductivity (often denoted k, λ, or κ)between the two interfaces between 1 W/mK to 300 W/mK at any temperaturebetween 0° C. and 100° C., or (iii) the object is a heat pipe, vaporchamber, body of copper, or body of aluminum. Examples of materialswhose thermal conductivity is between 1 W/mK to 300 W/mK at anytemperature between 0° C. and 100° C. include certain types of copper,aluminum, silver, and gold, for example.

For purposes of explanation, certain examples are described withreference to the components illustrated in FIGS. 1-6 . The functionalityof the illustrated components may overlap, however, and may be presentin a fewer or greater number of elements and components. Moreover, thedisclosed examples may be implemented in various environments and arenot limited to the illustrated examples. Further, the sequence ofoperations described in connection with FIGS. 4 and 6 is an example andis not intended to be limiting. Additional or fewer operations orcombinations of operations may be used or may vary without departingfrom the scope of the disclosed examples. Thus, the present disclosuremerely sets forth possible examples of implementations, and manyvariations and modifications may be made to the described examples. Suchmodifications and variations are intended to be included within thescope of this disclosure and protected by the following claims.

Electronic systems including, but not limited to, computers, serversystems, storage systems, wireless access points, network switches,routers, docking stations, printers, or scanners include circuitassemblies, each having one or more electronic circuit modules. Anelectronic circuit module includes several chipsets disposed on acircuit board, such as, a printed circuit board. Each chipset mayinclude one or more electronic chips (or electronic components orintegrated circuit chips). Examples of the electronic chips may include,but are not limited to, central processing unit (CPU) chips, graphicsprocessing unit (GPU) chips, power supply chips, memory chips, orelectronic elements, such as capacitors, inductors, resistors, or thelike. During operation of a circuit assembly, the electronic chips ofthe electronic circuit module may generate waste-heat (or heat). As willbe understood, such waste-heat is unwanted, and may have impact on theoperation of the electronic circuit module. For example, the waste-heatmay cause physical damage to the electronic chips, degrade performance,reliability, or life expectancy of the electronic circuit module havingsuch electronic chips, and in some cases the waste-heat may even causefailure of the circuit assembly.

In order to minimize the adverse effects of the waste-heat in theelectronic circuit module having several electronic chips, in certainimplementations, a thermal interface material, which is generallydisposed between each electronic chip and a frame supporting theelectronic circuit module is removed, as it reduces the electronicchip’s thermal resistance by several degrees. However, dealing with suchbare electronic chips are precarious, and may result in damagedelectronic chips, for example, cracked electronic chips when coolingmodules are improperly installed later-on in the factory, and especiallyin the field.

Therefore, in order to overcome such issues with the bare electronicchips, some electronic systems include a thermal management system todraw (or remove) the waste-heat away from the electronic chips. In someimplementations, the thermal management system may include coolingmodules that entail use of a cooling component (e.g., a cold plate) forremoving the waste-heat from the electronic chips. For example, thecooling component is disposed in contact (e.g., in a direct physicalcontact) with the electronic chips disposed on the circuit board toestablish a thermal interface between the cooling component and theelectronic chips. Accordingly, such cooling component absorbs thewaste-heat generated by the electronic chips, and transfers the absorbedwaste-heat away from the electronic chips.

However, in certain designs of the electronic circuit modules, theelectronic chips may have varied height resulting in an uneven topologyor a non-uniform topology of top surfaces of the electronic chips.Accordingly, in such implementations, the electronic chips disposed onthe circuit board may have different heights from the circuit board.Thus, the top surfaces of the electronic chips may be positioned atdifferent heights. In some other implementations, even though theelectronic chips disposed on the circuit board may have same heights,the top surfaces of the electronic chips may be positioned at differentheights due to one or more of soldering imperfections and variations inapplied pressures on the electronic chips by the cooling component toestablish the thermal interface therebetween. In certain other designsof the electronic circuit modules, some electronic chips may havevarying flatness (i.e., a non-uniform surface or an uneven surface) dueto design tolerances along their top surfaces, resulting in thenon-uniform topology or the uneven topology of the top surfaces of theelectronic chips. Accordingly, in such implementations, the electronicchips disposed on the circuit board may have uneven topology.

Consequently, when a common cooling component (i.e., a single coolingcomponent) is used in the electronic circuit module having such uneventopology among the top surfaces of the electronic chips disposedthereon, the common cooling component cannot be disposed in consistentcontact with the top surfaces of all electronic chips to establish aconsistent thermal interface therebetween. For example, such commoncooling component cannot come in contact with the electronic chipshaving lower height. Similarly, even when the common cooling componenthaving varied height (e.g., a complementary height to that of variedheight electronic chips) is used in the electronic circuit module havingvaried height electronic chips, the common cooling component cannot bedisposed in contact with the top surfaces of the electronic chips toestablish the thermal interface therebetween. For example, such commoncooling component cannot make consistent contact with the electronicchips having varying uneven topology.

Accordingly, any variations in at least one of the height or theflatness among the electronic chips in a module may result ininefficient cooling, and consequently varying chip temperatures acrossthe electronic circuit module. In other words, the common coolingcomponent may not effectively perform cooling of the electronic chipswith at least one of varied height or flatness. Further, any improperinstallation of the common cooling component on the electronic chipswith at least one of varied height or flatness, may result in damagingsome electronic chips. For example, the common cooling component may notapply a uniform pressure on all electronic chips to establish a thermalinterface therebetween, thus resulting in damage, such as cracking ofsome of the electronic chips.

Further, in certain implementations, the cooling module may direct acool fluid into a single-pass internal fluid chamber of the commoncooling component, which is in thermal contact with several electronicchips in order to dissipate the waste-heat from the several electronicchips irrespective of a case temperature of each of the severalelectronic chips. However, the cool fluid directed into the single-passinternal fluid chamber may have a low velocity, because of a high flowarea of the single-pass internal fluid chamber. Thus, the common coolingcomponent may have a reduced heat transfer co-efficient between the coolfluid and each of the several electronic chips. Therefore, to addresssuch issues related to the low velocity of the cool fluid, the coolingmodule may require to direct the cool fluid at a high volumetric flowrate into the single-pass internal fluid chamber. Hence, a coolantdistribution unit (CDU) of the thermal management system, which isfluidically connected to the common cooling component of the coolingmodule, may have to supply the cool fluid at the high volumetric flowrate. However, the CDU can deliver the cool fluid at high volumetricflow rate to only a fewer number of electronic systems, e.g., serversystems, thereby necessitating the thermal management system to utilizemultiple CDU’s to accommodate the cool fluid requirements of severalserver systems in a datacenter environment. Therefore, when the CDU isconfigured to deliver the cool fluid at high volumetric flow rate to thefewer number of server systems, then it may significantly increase CAPEXcost and operating cost of the datacenter environment. Also, thedatacenter environment may require more floor space to accommodate morenumber of CDU’s for catering the cool fluid requirements of serversystems.

Further, in one or more implementations, the fluid (e.g., the cool fluidor a partially hot fluid or a hot fluid) may need to have a thermalmargin to allow the fluid to efficiently absorb the waste-heat from theelectronic chip. As used herein, the term “thermal margin” may refer toa temperature difference between a case temperature of the electronicchip and the temperature of the fluid. Further, as used herein the term“case temperature” may refer to a maximum temperature that theelectronic chip may attain while operating to execute an assigned taskor a workload. In some examples, the cool fluid may have a sufficientthermal margin, (e.g., of about 4 degrees) as it flows in thermalcontact over one or more upstream electronic chips among the severalelectronic chips. Thus, the cool fluid can efficiently absorb thewaste-heat from the one or more upstream electronic chips among theseveral electronic chips, and generate the partially hot fluid or thehot fluid. As used herein the term “upstream electronic chips” may referto the electronic chips that are positioned proximate to a fluid inletof the common cooling component. However, the partially hot fluid or thehot fluid may not have the sufficient thermal margin, as it flows inthermal contact over one or more downstream electronic chips. Thus, thepartially hot fluid cannot efficiently absorb the waste-heat from theone or more downstream electronic chips among the several electronicchips. As used herein the term “downstream electronic chips” may referto the electronic chips that are positioned proximate to a fluid outletof the common cooling component. Therefore, the common cold componentmay not adequately or uniformly dissipate the waste-heat away from theall electronic chips.

One way in which the electronic industry is trying to address theaforementioned issues with common cooling components, is by using adiscrete (or a separate) cooling component for each electronic chipinstead of a common cooling component for the several electronic chips.However, a cooling module having such discrete cooling components mayincrease factory installation complexity and field and factoryserviceability challenges. For example, the circuit assembly may requiresubstantial plumbing modifications to include discrete coolingcomponents (e.g., separate cold plates) for each electronic chip. Insome implementations, the modifications may include i) drawing multipleflowlines into and out of each cooling component, and ii) implementing adiscrete fluid inlet connector and a discrete fluid outlet connector foreach cooling component. Additionally, during a service or aninstallation event, technicians may need to follow complicated processesto complete the connection (or disconnection) of the discrete fluidinlet and outlet of each cooling component, to a respective flowline ofthe multiple flowlines.

Further, in some implementations, the discrete cooling components may beinterconnected using external pipelines, so as to reduce the complexityof installation and serviceability. However, directing the cool fluidbetween the discrete cooling components via the external pipelines mayresult in a higher pressure drop within each cooling component. Thus, insuch implementations, the CDU may consume more power to maintain arequired volumetric flow rate, to account for associated pressure dropin each cooling component. This may affect the CDU’s ability to supplythe cool fluid to the several server systems of the datacenterenvironment. Additionally, the cooling module having external pipelinesmay occupy more space within each server system.

In accordance with aspects of the present disclosure, an improvedcooling module is provided for electronic circuit modules of a circuitassembly that mitigates one or more challenges noted hereinabove. Forexample, the improved cooling module includes a first cooling component,and a second cooling component positioned within a recess portion of thefirst cooling component. In some examples, the first cooling componentis mounted on a frame of the circuit assembly supporting the electroniccircuit module, to fluidically connect to the second cooling componentand establish a first thermal interface with a first electronic chipsetof the electronic circuit module. Similarly, the second coolingcomponent is mounted on the frame to establish a second thermalinterface with a second electronic chipset of the electronic circuitmodule. In such examples, the first cooling component may independentlymove (e.g., float) 3-dimensionally relative to the second coolingcomponent, upon mounting of the first cooling component to the frame, toaccommodate variations in at least one of a height or a flatness betweenthe first and second electronic chipsets. In some examples, the firstcooling component may tilt relative to the second cooling component toalign with a surface of the second cooling component to accommodate thevariation in the flatness between the first and second electronicchipsets. In some other examples, the first cooling component may moveup and down relative to the second cooling component to accommodate thevariation in the height between the first and second electronicchipsets. In one or more examples, the first cooling component may tiltrelative to the second cooling component to accommodate variation in theflatness between the first and second electronic chipsets, move up anddown relatively to the second cooling component to accommodate variationin the height between the first and second electronic chipsets, or acombination thereof.

In one or more examples, the first cooling component includes a pair offirst fluid connectors and the second cooling component includes a pairof second fluid connectors. In such examples, each connector of the pairof first fluid connectors is movably connected to a respective connectorof the pair of second fluid connectors to establish a fluid-flow pathbetween the first and second cooling components. In some examples, eachconnector of the pair of first fluid connectors is one of a fluid boreor a fluid piston. Similarly, each connector of the pair of second fluidconnectors is the other one of the fluid bore or the fluid piston. Insuch examples, the cooling module further includes an O-ring sealdisposed in an outer circumferential groove of the fluid piston. In oneor more examples, the O-ring seal may contact a wall (i.e., compressedagainst the wall) of the fluid bore, when the fluid piston is movablyconnected to the fluid bore to establish the fluid-flow path between thefirst and second cooling components, so as to prevent leakage of a fluid(a partially hot fluid or a hot fluid) from the fluid-flow path. In someexamples, the O-ring seal (in the compressed state against the wall) mayslide along the wall (inner wall) of the fluid bore by an up and downmovement of the first cooling component relative to the second coolingcomponent. In some other examples, the O-ring seal is eccentricallycompressed against the wall (inner wall) of the fluid bore by a tiltingmovement of the first cooling component relative to the second coolingcomponent. In other words, when the first cooling component is tilted toaccommodate variations in the flatness between the first and secondelectronic chips, the O-ring seal may get eccentrically compressed by adisplacement of the first cooling component relative to the firstelectronic chipset. In one or more examples, the O-ring seal slidesalong the wall of the fluid bore by the up and down movement of thefirst cooling component relative to the second cooling component,eccentrically compresses against the wall of the fluid bore, by thetilting movement of the first cooling component relative to the secondcooling component, or a combination thereof.

The first cooling component receives the fluid (a cool fluid) from acoolant distribution unit (CDU) of a thermal management system in adatacenter environment. In such examples, the first cooling componentdirects the cool fluid within a first fluid channel of the first coolingcomponent to absorb the waste-heat from the first electronic chipset andgenerate the partially hot fluid. The first cooling component furtherdischarges the partially hot fluid to an intermediate channel of thesecond cooling component via the fluid-flow path (e.g., an inletfluid-flow path). In such examples, the second cooling component directsthe partially hot fluid within the intermediate channel of the secondcooling component to absorb the waste-heat from the second electronicchipset and generate the hot fluid. Later, the second cooling componentdischarges the hot fluid to a second fluid channel of the first coolingcomponent via the fluid-flow path (e.g., an outlet fluid-flow path). Thefirst cooling component directs the hot fluid in the second fluidchannel to return the hot fluid outside the cooling module. In someexamples, the first fluid channel includes a body section having atortuous flow route disposed in thermal contact with the firstelectronic chipset. For example, the body section is first bifurcatedinto a first body section and a second body section, and later the firstand second body sections are merged into a third body section to definethe tortuous flow route for the body section. In one or more examples,the body section having the tortuous flow route may significantlyincrease a velocity of the fluid within the first cooling component toefficiently dissipate the waste-heat from a high powered electronicchipset or the first electronic chipset (e.g., a plurality of memorychips (or a plurality of first electronic chip), and a GPU chip (or asecond electronic chip)). Thus, the CDU may be allowed to deliver thecool fluid to the first cooling component of the cooling module, at alow volumetric flow rate for cooling the first electronic chipset.Further, the intermediate fluid channel having a single-pass flow routeis disposed in thermal contact with the second electronic chipset. Inone or more examples, the intermediate fluid channel having thesingle-pass flow route may enable the fluid to be directed at arelatively low velocity to effectively dissipate the waste-heat from alow powered electronic chipset or the second electronic chipset (e.g., aCPU chip or the third electronic chip). In some examples, the bodysection of the first fluid channel having the tortuous flow route mayenable the cooling module to have the volumetric flow rate of about 0.12gallons per minutes. Accordingly, the CDU in the datacenter environmentmay be enabled to accommodate the cool fluid requirement of multipleserver systems of the datacenter environment. In some examples, the CDUmay be provisioned to supply the cool fluid for multiple racks, forexample, to at least four racks, where each rack may have aboutthirty-two server systems, and each server system may have about eightcircuit assemblies, and each circuit assembly may have at least onecooling module.

In some examples, since the cool fluid is first directed to thebifurcated fluid sections, which are in thermal contact with theplurality of first electronic chips having the low case temperature, thecool fluid may have a sufficient thermal margin to efficiently dissipatethe waste-heat from the plurality of first electronic chips. Further,since a mixed portion of the partially hot fluid from the bifurcatedfluid sections, is directed to the merged body section, which is inthermal contact with the second electronic chip having the high casetemperature, the mixed portion of the partially hot fluid may still havethe sufficient thermal margin to efficiently dissipate the waste-heatfrom the second electronic chip. Further, since the partially hot fluidfrom the first cooling component is directed to the intermediate fluidchannel, which is in thermal contact with the third electronic chiphaving the highest case temperature, the partially hot fluid may stillhave the sufficient thermal margin to efficiently dissipate thewaste-heat from the third electronic chip. Therefore, the cooling modulemay be able to adequately and uniformly dissipate the waste-heat awayfrom the all electronic chips in the electronic circuit module.

Accordingly, the present disclosure describes example implementations ofa cooling module for an electronic circuit module of a circuit assembly,and a method of cooling the electronic circuit module. The coolingmodule includes a first cooling component and a second coolingcomponent. The first cooling component includes a pair of first fluidconnectors and an intermediate fluid channel. The second coolingcomponent includes a first fluid channel and a second fluid channel,where the first fluid channel includes a supply section, a returnsection, and a body section. The second cooling component is positionedwithin a recess portion of the first cooling component and fluidicallyconnected to the first cooling component. The body section is bifurcatedinto a first body section and a second body section, and the first andsecond body sections are further merged into a third body section. Thesupply section is connected to the first and second body sections. Thereturn section is connected to the third body section and theintermediate fluid channel via an inlet fluid-flow path establishedbetween the first and second cooling components. The second fluidchannel is connected to the intermediate fluid channel via an outletfluid-flow path established between the first and second coolingcomponents.

Referring to the Figures, FIG. 1A depicts an exploded perspective viewof a circuit assembly 100. FIG. 1B depicts an assembled perspective viewof the circuit assembly 100 of FIG. 1A. FIG. 1C depicts a crosssectional view of one connector 164A of a pair of first fluid connectors164 having an O-ring seal 182, movably connected to another connector148A of a pair of second fluid connectors 148 of FIGS. 1A-1B inaccordance to one example of the present disclosure. FIG. 1D depicts across sectional view of one connector 164A of the pair of first fluidconnectors 164 having the O-ring seal 182, movably connected to theother connector 148A of the pair of second fluid connectors 148 of FIGS.1A-1B in accordance to another example of the present disclosure. In thedescription hereinafter, the Figures, FIGS. 1A-1D and FIGS. 2A-2G aredescribed concurrently for ease of illustration.

The circuit assembly 100 may function as an electronic package unitconfigured to provide mechanical protection to an electronic circuitmodule 104, dissipate waste-heat from the electronic circuit module 104,and distribute electrical energy for the functioning of the electroniccircuit module 104 to execute at least one workload. In some examples,the circuit assembly 100 includes a frame 102, the electronic circuitmodule 104, and a cooling module 106. In one or more examples, thecircuit assembly 100 may be disposed within an electronic system, suchas, but not limited to, a server system, a storage system, an accesspoint, a network switch, a router, a docking station, a printer, or ascanner to execute the at least one workload. In certain examples, thecircuit assembly 100 is a compute node of the electronic system, such asa server system. In such examples, a plurality of compute nodes may bedisposed within a chassis of the server system, and a plurality of suchserver systems may be deployed in an enclosure or a rack or a tray of adatacenter environment (not shown) to execute a plurality of workloads.As discussed herein, the circuit assembly 100 includes the electroniccircuit module 104 coupled to the frame 102, and the cooling module 106assembled to the electronic circuit module 104 and connected to theframe 102.

Referring FIGS. 1A-1B, the frame 102 may function as a stiffener and aheat transfer plate of the circuit assembly 100. In some examples, theframe 102 includes a base portion 102A and a cover portion 102B. FIG. 2Ain particular depicts an exploded perspective view of the frame 102. Insome examples, the base portion 102A is an open-box shaped element. Insuch examples, the base portion 102A has a floor section 112A forsupporting a circuit board 128 (as shown in FIG. 1A) of the electroniccircuit module 104. The floor section 112A of the base portion 102Aincludes a plurality of first clamping holes 114A. Further, the baseportion 102A may include a plurality of retainer holes (not shown)formed in the floor section 112A. In such examples, the plurality ofretainer holes may be used to clamp the frame 102 to the electronicsystem. In some examples, the cover portion 102B is another open-boxshaped element. In such examples, the cover portion 102B has an opening110 formed in a lid section 112B of the cover portion 102B. For example,the opening 110 may be formed substantially at a center portion of thelid section 112B. Additionally, the lid section 112B includes aplurality of first holes 118A, a plurality of second holes 118B, and aplurality of second clamping holes 114B. In some examples, each hole ofthe plurality of second clamping holes 114B is aligned to a respectivehole of the plurality of first clamping holes 114A in the base portion102A. In one or more examples, the cover portion 102B may be mounted onand coupled to the base portion 102A to form the frame 102.

Referring to FIGS. 1A-1B, the electronic circuit module 104 may functionas a multi-chip module of the circuit assembly 100. In some examples,the electronic circuit module 104 includes a first chipset 124 (or firstelectronic chipset), a second chipset 126 (or second electronicchipset), and a circuit board 128. FIG. 2B in particular depicts aperspective view of the electronic circuit module 104. In some examples,the circuit board 128 may be a printed circuit board (PCB) that includesseveral electrical conductive traces (not shown) to electricallyinterconnect the first and second electronic chipsets 124, 126,respectively. In some examples, the first and second electronic chipsets124, 126 respectively, are positioned adjacent to each other, anddisposed on and coupled to the circuit board 128. For example, the firstand second electronic chipsets 124, 126 may be coupled to the circuitboard 128 by solder joints. In some examples, the first electronicchipset 124 includes a plurality of first electronic chips 124A and asecond electronic chip 124B. Similarly, the second electronic chipset126 includes a third electronic chip 126A. It may be noted herein thatthe plurality of first electronic chips 124A, the second electronic chip124B, and the third electronic chip 126A may be collectively referred toas electronic chips 125 (as labeled in FIG. 2B). Examples of theelectronic chips 125 may include, but are not limited to, centralprocessing unit (CPU) chips, graphics processing unit (GPU) chips, powersupply chips, memory chips, or other electronic elements, such ascapacitors, inductors, resistors, or the like. In the illustratedexample, each of the plurality of first electronic chips 124A is amemory chip, the second electronic chip 124B is a graphics chip, and thethird electronic chip 126A is a processor (CPU) chip. In the example ofFIG. 2B, the plurality of first electronic chips 124A is arranged alonga first row 127A and a second row 127B located around the secondelectronic chip 124B. It is to be noted that the electronic circuitmodule 104 may include various combinations of different types ofelectronic chips 125, without limiting the scope of the presentdisclosure. Further, while the electronic circuit module 104 is shown toinclude three types of electronic chips 125 arranged in a specificfashion, the scope of the present disclosure is not limited with respectto the number or types of electronic chips 125 and the manner in whichthe electronic chips 125 are laid out on the circuit board 128. Thecircuit board 128 additionally includes a plurality of third clampingholes 114C, each aligned to respective holes of the plurality of firstand second clamping holes 114A, 114B respectively, of the frame 102.

FIG. 2C in particular depicts a cross sectional view of the electroniccircuit module 104 taken along line 1-1′ in FIG. 2B. The firstelectronic chipset 124 (e.g., the plurality of first electronic chips124A and/or the second electronic chip 124B) may have an even flatness“F₁” along its top surface 134. For example, the even flatness “F₁” isabout 0 degrees. Further, the first electronic chipset 124 may have afirst height “H₁” from the top surface 132 of the circuit board 128.Similarly, the second electronic chipset 126 (e.g., the third electronicchip 126A) may have a varied flatness “F₂” along its top surface 130. Insome examples, the varied flatness “F₂” may be about -5 degrees.Further, the third electronic chipset 126 may have a second height “H₂”from a top surface 132 of the circuit board 128. In the illustratedexample of FIG. 2C, the first height “H₁” is greater than the secondheight “H₂”. Accordingly, in the illustrated example, the first andsecond electronic chipsets 124, 126 respectively have varied height andflatness. In one or more examples, the top surface 134 of the firstelectronic chipset 124 is a first thermal interfacing surface 134A ofthe electronic circuit module 104, and the top surface 130 of the secondelectronic chipset 126 is a second thermal interfacing surface 130A ofthe electronic circuit module 104.

Referring to FIGS. 1A-1B, the cooling module 106 functions as a fluidcooling module of the circuit assembly 100, which entails use of a coolfluid 198A (or fluid, as shown in FIGS. 5A-5B) to take away thewaste-heat from the electronic chips 125 of the electronic circuitmodule 104 and generate a hot fluid 198C (as shown in FIGS. 5A-5B).Examples of the cool fluid 198A include, but are not limited to a coolliquid-coolant, a cool gaseous-coolant, or combinations thereof. Forexample, the cool liquid-coolant may have about 25 percent of propyleneglycol and 75 percent of water. In some examples, the temperature of thecool fluid 198A may be about 36 degrees, which is known as a supplytemperature or a secondary temperature, the temperature of the hot fluid198C may be about 60 degrees, which is known as a return temperature ora tertiary temperature, and the temperature of a facility fluid (notshown) may be about 32 degrees, which is known as a facility temperatureor a primary temperature. As used herein, the term “supply temperature”may refer to the temperature of the cool fluid 198A delivered from acoolant distribution unit (CDU, not shown) to the cooling module 106 ofeach circuit assembly 100. Similarly, the term “return temperature” mayrefer to the temperature of the hot fluid 198C discharged from thecooling module 106 of each circuit assembly 100 to the CDU. Further, theterm “facility temperature” may refer to the temperature of the facilityfluid directed from a datacenter environment to the CDU for cooling thehot fluid 198C received from the cooling module 106. In one or moreexamples, the CDU may include at least one heat exchanger system toenable transfer of the waste-heat from the hot fluid 198C to thefacility fluid in order to regenerate the cool fluid 198A. In one ormore examples, the supply temperature of the cool fluid 198A may be acombination of the facility temperature of the facility fluid, and anapproach temperature of the heat exchanger in the CDU. In some examples,the approach temperature may be a rise in temperature of the cool fluid198A or a difference in temperature between the cool fluid 198A and thefacility fluid.

In some examples, the cooling module 106 includes a first coolingcomponent 136 and a second cooling component 138. In some examples, eachof the first and second cooling components 136, 138 respectively, is athermally conductive component, for example, a cold plate. In suchexamples, each of the first and second cooling components 136, 138respectively, has internal channels or fluid channels, such asmicro-channels (not shown in FIGS. 1A-1B) for guiding (or directing) thecool fluid 198A to absorb the waste-heat, and generate a hot fluid 198C.

FIG. 2D depicts an exploded top view of the cooling module 106, and FIG.2E depicts an exploded bottom view of the cooling module 106. In one ormore examples, the first cooling component 136 includes a pair of firstflange portions 152, a recess portion 154 located between the pair offirst flange portions 152, and a pair of first fluid connectors 164. Insome examples, the first cooling component 136 has a top surface 156 anda bottom surface 158. The first cooling component 136 further includes afirst cooling portion 160 and a third cooling portion 162. In someexamples, the first cooling portion 160 is formed at the bottom surface158 corresponding to a portion of a first flange 152A of the pair offirst flange portions 152. In such examples, the first cooling portion160 protrudes outwards from the bottom surface 158 of the first coolingcomponent 136. In one or more examples, a bottom surface of the firstcooling portion 160 functions as a first thermal interfacing surface160A of the cooling module 106. In some examples, the first coolingportion 160 has a height that is substantially greater than a height ofeach flange of the pair of first flange portions 152. Further, eachflange of the pair of first flange portions 152 has equal height. Thethird cooling portion 162 is formed on the top surface 156 of the firstcooling component 136. For example, the third cooling portion 162protrudes outwards from the top surface 156 and extends between the pairof first flange portions 152 and the recess portion 154. In someexamples, the third cooling portion 162 has a height that issubstantially greater than the height of each flange of the pair offirst flange portions 152. The first cooling component 136 furtherincludes a fluid inlet 166 and a fluid outlet 168 spaced apart from eachother and formed in a first peripheral wall 162A of the third coolingportion 162.

In one or more examples, the pair of first fluid connectors 164 isformed at the bottom surface 158. For example, the pair of first fluidconnectors 164 is located at the recess portion 154, where eachconnector of the pair of first fluid connectors 164 protrudes inwardstowards the third cooling portion 162 from the recess portion 154. Insome examples, the pair of first fluid connectors 164 includes a firstconnector 164A, and a second connector 164B. In one or more examples,the first connector 164A may be fluidically connected to the fluid inlet166 via a first fluid channel 192 (as shown in FIGS. 5A-5B) formedwithin the first cooling portion 160 and the third cooling portion 162of the first cooling component 136. Similarly, the second connector 164Bmay be fluidically connected to the fluid outlet 168 via a second fluidchannel 196 (as shown in FIGS. 5A-5B) formed within the third coolingportion 162 of the first cooling component 136. In some examples, thepair of first fluid connectors 164 may be one of a fluid bore or a fluidpiston. In the examples of FIGS. 2D-2E, each connector of the pair offirst fluid connectors 164 is the fluid bore. It may be noted hereinthat the fluid bore is discussed in greater details in the examples ofFIGS. 1C-1D.

The first cooling component 136 further includes a plurality of fourthholes 118D formed in the first flange 152A of the pair of first flangeportions 152. In one or more examples, each fourth hole of the pluralityof fourth holes 118D is aligned with a respective second hole of theplurality of second holes 118B formed in the cover portion 102B of theframe 102. Further, each fourth hole of the plurality of fourth holes118D has a diameter that is substantially equal to the diameter of eachsecond hole of the plurality of second holes 118B.

In some examples, the first cooling component 136 further includes aplurality of fifth holes 118E formed in the recess portion 154.Additionally, the first cooling component 136 includes a plurality offourth clamping holes 114D. Each hole of the plurality of fourthclamping holes 114D is aligned to a respective hole of the plurality ofsecond clamping holes 114B formed in the cover portion 102B of the frame102. Further, each hole of the plurality of fourth clamping holes 114Dhas a diameter that is substantially greater than a diameter of eachrespective hole of the plurality of first, second, and third clampingholes 114A, 114B, 114C. Further, each hole of the plurality of first,second, and third clamping holes 114A, 114B, 114C respectively, haveequal diameter.

The first cooling component 136 additionally includes a plurality ofretention holes 170 (or a plurality of retention bores) spaced apartfrom each other, and formed on the third cooling portion 162 of thefirst cooling component 136. For example, each retention hole of theplurality of retention holes 170 is located in the recess portion 154and extends along the third cooling portion 162. Each retention hole ofthe plurality of retention holes 170 is aligned to a respectiveretention tab of the plurality of retention tabs 150 formed in thesecond cooling component 138. In some examples, each retention hole ofthe plurality of retention holes 170 has a diameter, which issubstantially equal to a diameter/width of a respective retention tab ofthe plurality of retention tabs 150.

The first cooling component 136 further includes a plurality of captivefastener holes 172 (or a plurality of captive fastener bores) formed inperipheral walls of the third cooling portion 162. For example, one pairof captive fastener holes 172A is formed in the first peripheral wall162A of the third cooling portion 162 and another pair of captivefastener holes (not shown) is formed in a second peripheral wall 162B ofthe third cooling portion 162. In some examples, each captive hole ofthe plurality of captive fastener holes 172 may extend up to arespective retention hole of the plurality of retention holes 170. Eventhough not illustrated in the examples of FIGS. 1A-1B, it may be notedherein, that each captive fastener hole 172 is a stepped hole (or bore).In one or more examples, each captive fastener 178 (as shown in FIG. 2E)may be retained freely inside the captive fastener hole (stepped hole)without getting the respective captive fastener 178 lost from the firstcooling component 136, and at the same time the stepped hole may allowthe respective captive fastener 178 to be selectively fastened to engage(or disengage) with the respective retention tab 150 to couple (ordecouple) the first and second cooling components 136, 138 respectively,to each other.

In one or more examples, the second cooling component 138 includes apair of second flange portions 140, a second cooling portion 142 locatedbetween the pair of second flange portions 140, and a pair of secondfluid connectors 148. In some examples, the second cooling component 138has a top surface 144 and a bottom surface 146. In such examples, thesecond cooling portion 142 is formed at the bottom surface 146. Forexample, the second cooling portion 142 protrudes outwards from thebottom surface 146 of the second cooling component 138. In one or moreexamples, a bottom surface of the second cooling portion 142 functionsas a second thermal interfacing surface 142A of the cooling module 106.In some examples, the second cooling portion 142 has a height that issubstantially greater than a height of each flange of the pair of secondflange portions 140. Further, each flange of the pair of second flangeportions 140 has equal height.

In some examples, the pair of second fluid connectors 148 is formed atthe top surface 144 of the second cooling component 138. For example,the pair of second fluid connectors 148 protrudes outwards from the topsurface 144. The pair of second fluid connectors 148 includes anotherfirst connector 148A of pair of second fluid connectors 148, and anothersecond connector 148B of the pair of second fluid connectors 148. In oneor more examples, the other first connector 148A of the second coolingcomponent 138 is aligned with the first connector 164A of the firstcooling component 136. Similarly, the other second connector 148B of thesecond cooling component 138 is aligned with the second connector 164Bof the first cooling component 136. In one or more examples, the pair ofsecond fluid connectors 148 is fluidically connected to an intermediatefluid channel 194 (see, FIGS. 5A-5B) formed within the second coolingportion 142 of the second cooling component 138. For example, the otherfirst connector 148A may be connected to one end portion 184 (as shownin FIG. 1C) of the intermediate fluid channel 194, and the other secondconnector 148B may be connected to another end (not shown) of theintermediate fluid channel 194. In some examples, the pair of secondfluid connectors 148 may be the other one of the fluid bore or the fluidpiston. In the examples of FIGS. 2D-2E, each connector of the pair ofsecond fluid connectors 148 is the fluid piston. It may be noted hereinthat the fluid piston is discussed in greater details in the examples ofFIGS. 1C-1D.

The second cooling component 138 further includes a plurality of thirdholes 118C. For example, each flange of the pair of second flangeportions 140 may include a pair of third holes among the plurality ofthird holes 118C. In one or more examples, each third hole of theplurality of third holes 118C is aligned with a respective first hole ofthe plurality of first holes 118A formed in the cover portion 102B ofthe frame 102. Further, each third hole of the pair of third holes 118Cis aligned to a respective fifth hole of the plurality of fifth holes118E formed in the first cooling component 136. In one or more examples,each fifth hole of the plurality of fifth holes 118E has a diameter thatis substantially greater than the i) diameter of the each third hole ofthe plurality of third holes 118C formed in the second cooling component138 and ii) diameter of each first hole of the plurality of first holes118A formed in the cover portion 102B of the frame 102. Similarly, eachthird hole of the plurality of third holes 118C has a diameter that issubstantially equal to the diameter of each first hole of the pluralityof first holes 118A. The second cooling component 138 further includes aplurality of retention tabs 150 spaced apart from each other and formedon the top surface 144 of the second cooling component 138. For example,each retention tab of the plurality of retention tabs 150 extendsoutwards from the top surface 144 of the second cooling component 138.

Referring to FIGS. 1A-1B, the example cooling module 106 furtherincludes a plurality of first spring loaded fasteners 174 and aplurality of second spring loaded fasteners 176. In one or moreexamples, each fastener of the plurality of first spring loadedfasteners 174 may be inserted through respective holes of the pluralityof fourth and second holes 118D, 118B respectively, to connect the firstcooling component 136 to the frame 102. Similarly, each fastener of theplurality of second spring loaded fasteners 176 may be inserted throughrespective holes of the plurality of third and first holes 118C, 118Arespectively, to connect the second cooling component 138 to the frame102. Referring to the Figure, FIG. 2F depicts one spring loaded fasteneramong the plurality of first spring loaded fasteners 174, for example.It may be noted herein that the first and second spring loaded fasteners174, 176 are substantially similar. Referring to the Figure, FIG. 2F inparticular, the first spring loaded fastener 174 includes a shoulderscrew 174A and a spring 174B. The shoulder screw 174A includes a headportion 174A₁, a shank portion 174A₂, and a thread portion 174A₃. Insuch examples, the head portion 174A₁ has a diameter greater than adiameter of the shank portion 174A₂ and the thread portion 174A₃.Further, the shank portion 174A₂ has a diameter that is greater than adiameter of the thread portion 174A₃. The spring 174B is a helicalcompression spring mounted to the shank portion 174A₂. In one or moreexamples, the thread portion 174A₃ of the first spring loaded fastener174 may be fastened into the second hole 118B of the cover portion 102Bof the frame 102, in order to connect the first cooling component 136 tothe frame 102. In such examples, the spring 174B may get compressed bysuch fastening of the thread portion 174A₃ into the first hole 118A,thereby causing the spring 174B to bias the first cooling component 136to move towards the first electronic chipset 124 to establish a thermalinterface with the first electronic chipset 124.

Accordingly, in one or more examples, each spring 174B in the pluralityof first spring loaded fasteners 174 may individually bias the firstcooling component 136 to move towards the first electronic chipset 124to establish a first thermal interface with the first electronic chipset124. Similarly, each spring in the plurality of second spring loadedfasteners 176 may individually bias the second cooling component 138 tomove towards the second electronic chipset 126 to establish a secondthermal interface with the second electronic chipset 126.

Referring to the Figures, FIGS. 1A, 2E, and 2G, the cooling module 106further includes a plurality of captive fasteners 178. In some examples,each captive fastener 178 is a special type of screw that may remainfreely inside an opening of an object, for example, the captive fastenerhole 172 without getting lost from the captive fastener hole 172, and atthe same time the captive fastener 178 may be selectively fastened tolock the first cooling component 136 to the second cooling component138. In some examples, the captive fastener 178 includes a head portion178A, an intermediary portion 178B, an end portion 178C, a first bodyportion 178D connecting the head and intermediary portions 178A, 178B,and a second body portion 178E connecting the intermediary portion 178Band the end portion 178C. The head and intermediary portions 178A, 178Bhas substantially equal diameter. The first and second body portions178D, 178E has substantially equal diameter. The intermediary portion178B may have a diameter greater than the diameter of the captivefastener hole 172, thereby freely retaining the captive fastener 178within the captive fastener hole 172. The second body portion 178E mayhave threads to move relative to counter threads formed in the captivefastener hole 172. Further, the end portion 178C of the captive fastener178 may get engaged with the retention tab 150 of the second coolingcomponent 138 (see, FIG. 3 ) in order to couple the first and secondcooling components 136, 138 to one another.

Although the circuit assembly 100 of FIGS. 1A-1B is shown to include onecooling module 106, use of more than one cooling modules in the circuitassembly 100 is also contemplated within the scope of the presentdisclosure. The cooling module 106 presented herein is a fluid coolingmodule that entails use of the cool fluid 198A to take away thewaste-heat from the electronic chips 125 and generate the hot fluid198B. For ease of illustration, other components and devices of athermal management system (e.g., CDU, manifolds, flowlines, coolantcirculation pumps, valves, etc.) used to enable a flow of the cool fluid198A from the CDU to the cooling module 106, and the flow of the hotfluid 198B to the CDU are not shown in FIGS. 1A-1B, and are consideredto be out of the scope of the present disclosure.

Referring to FIGS. 1A-1B and FIGS. 2A-2C, during assembly of the coolingmodule 106, the electronic circuit module 104 is disposed on the baseportion 102A of the frame 102 such that the circuit board 128 is seatedon the floor section 112A of the base portion 102A, and each hole of theplurality of third clamping holes 114C is aligned to the respective holeof the plurality of first clamping holes 114A in the base portion 102A.Further, the cover portion 102B of the frame 102 is mounted in the baseportion 102A such that the first electronic chipset 124 and the secondelectronic chipset 126 are accessible from the opening 110 in the coverportion 102B. Further, each second hole of the plurality of secondclamping holes 114B in the cover portion 102B is aligned to therespective hole of the plurality of third clamping holes 114C in thecircuit board 128. Later, a clamping fastener of a plurality of clampingfasteners (not shown) is inserted into respective clamping holes of theplurality of second, third, and first clamping holes 114B, 114C, 114Arespectively, in the cover portion 102B, the circuit board 128, and thebase portion 102A respectively, so as to couple the cover portion 102Bto the base portion 102A and form the frame 102 having the electroniccircuit module 104 sandwiched therebetween.

As discussed in the example of FIG. 2C, the electronic chips 125 (e.g.,the first electronic chipset 124 and the second electronic chipset 126)may have at least one of the varied height (“H₁”, “H₂”) or flatness(“F₁”, “F₂”) resulting in an uneven topology of respective top surfaces134, 130. For example, in some implementations, the first electronicchipset 124 and the second electronic chipset 126 disposed on thecircuit board 128 may have different heights “H₁” and “H₂” respectively,as shown in FIG. 2C. Accordingly, the top surfaces 134, 130 of the firstand second electronic chipsets 124, 126 respectively may be positionedat different heights. Similarly, the first and second electronicchipsets 124, 126 respectively, may have different flatnesses “F₁” and“F₂” respectively, due to design tolerances, or the like, as shown inFIG. 2C. In certain other implementations, even though the first andsecond electronic chipsets 124, 126 disposed on the circuit board 128may have the same height, the top surfaces 134, 130 of the first andsecond electronic chipsets 124, 126 may be positioned at differentheights due to one or more of soldering imperfections, or variations inapplied pressures on the first and second electronic chipsets 124, 126.

In accordance with the aspects of the present disclosure, the coolingmodule 106 facilitates to accommodate such variations in at least one ofthe flatness or the height between the first and second electronicchipsets 124, 126, as discussed herein below. Thus, referring to theFigures, FIGS. 1A-1B and 2D-2E, the second cooling component 138 ismounted on the frame 102 such that the second cooling portion 142 of thesecond cooling component 138 faces the second electronic chipset 126 ofthe circuit board 128. In some examples, upon mounting of the secondcooling component 138 on the frame 102, the second thermal interfacingsurface 142A of the second cooling component 138 may align with thesecond thermal interfacing surface 130A of the second electronic chipset126. As discussed, in the example of FIG. 2C, since the second thermalinterfacing surface 130A of the second electronic chipset 126 has unevenflatness “F₂”, the second thermal interfacing surface 142A of the secondcooling component 138 may align to it, thereby resulting in the topsurface 144 of the second cooling component 138 to be tilted. Later,each fastener of the plurality of second spring loaded fasteners 176 isinserted into the respective third hole 118C in the second coolingcomponent 138 and to the respective first hole 118A in the cover portion102B to connect the second cooling component 138 to the frame 102. Insome examples, each spring of the plurality of second spring loadedfasteners 176 may bias the second cooling component 138 to move towardsthe second electronic chipset 126, thereby establishing a second thermalinterface between the second thermal interfacing surfaces 142A, 130A ofthe second cooling component 138 and the second electronic chipset 126.

Further, the first cooling component 136 is positioned over the secondcooling component 138 such that the plurality of retention holes 170 inthe first cooling component 136 is aligned with the plurality ofretention tabs 150 of the second cooling component 138. Later, the firstcooling component 136 is mounted on the frame 102 with the first coolingportion 160 of the first cooling component 136 facing the firstelectronic chipset 124 of the circuit board 128. In such examples, whenthe first cooling component 136 is mounted on the frame 102, the secondcooling component 138 is positioned within the recess portion 154 of thefirst cooling component 136, and each retention tab of the plurality ofretention tabs 150 protrudes along a respective hole of the plurality ofretention holes 170.

Further, upon mounting of the first cooling component 136 on the frame102, as discussed herein, each connector of the pair of first fluidconnectors 164 in the first cooling component 136 is movably connectedto a respective connector of the pair of second fluid connectors 148 inthe second cooling component 138 to establish a fluid-flow path 190(see, FIG. 1C) between the first and second cooling components 136, 138.For example, the first connector 164A of the pair of first fluidconnectors 164 is movably connected to the other first connector 148A ofthe pair of second fluid connectors 148 to establish an inlet fluid-flowpath 190A (see, FIGS. 5A-5B) between the first and second coolingcomponents 136, 138. Similarly, the second connector 164B of the pair offirst fluid connectors 164 is movably connected to the other secondconnector 148B of the pair of second fluid connectors 148 to establishan outlet fluid-flow path 190B (see, FIGS. 5A-5B) between the first andsecond cooling components 136, 138.

In some examples, mounting of the first cooling component 136 on theframe 102 causes the first cooling component 136 to move up (and down)relative to the second cooling component 138 to accommodate thevariation in the height (“H₁” “H₂”) between the first and secondelectronic chipsets 124, 126. Further, mounting of the first coolingcomponent 136 on the frame 102 may additionally cause the first coolingcomponent 136 to tilt relative to the second cooling component 1386 toalign with the top surface 144 of the second cooling component 138 so asto accommodate the variation in the flatness (“F₁”, “F₂”) between thefirst and second electronic chipsets 124, 126. In some examples,mounting of the first cooling component 136 on the frame 102 may causeboth a tilting movement, and an up and down movement of the firstcooling component 136 relative to the second cooling component 138 toaccommodate the variation in the flatness and the height respectively,between the first and second electronic chipsets 124, 126. In suchexamples, each retention tab of the plurality of retention tabs 150 mayslide along the respective retention hole of the plurality of retentionholes 170 so as to align the first cooling component 136 with the secondcooling component 138.

Referring to FIGS. 1C-1D, in some examples, the first connector 164A ofthe pair of first fluid connectors 164 is a fluid bore 164A₁. In suchexamples, the fluid bore 164A₁ has a first diameter “D₁”. In someexamples, the first diameter “D₁” is about 0.486 inches to about 0.544inches. The fluid bore 164A₁ is connected to one end 188 of the firstfluid channel 192 (as shown in FIGS. 5A-5B) of the second coolingcomponent 138. In some other examples, the first connector 164A of thepair of first fluid connectors 148 may be a fluid piston.

In some examples, the other first connector 148A of the pair of secondfluid connectors 148 is a fluid piston 148A₁. In such examples, thefluid piston 148A₁ has a wall 186 (or circumferential wall) and a seconddiameter “D₂” and an outer circumferential groove 180 formed on aportion of the fluid piston 148A₁ has a groove diameter “D₃”. In someexamples, the second diameter “D₃” is about 0.483 inches to about 0.538inches. Similarly, the groove diameter “D₂” is about 0.376 inches toabout 0.378 inches. In some other examples, the other first connector148A of the pair of second fluid connectors 148 may be the fluid bore.In some examples, the second diameter “D₂” is greater than the firstdiameter “D₁”. The cooling module 106 further includes an O-ring seal182 disposed in the outer circumferential groove 180 of the fluid piston148A₁. In some examples, an inner diameter of the O-ring seal 182 may bearound 0.359 inches to about 0.367 inches. In some examples, the fluidpiston 148A₁ is connected to one end portion 184 of the intermediatefluid channel 194 (as shown in FIGS. 5A-5B) of the first coolingcomponent 136.

In one or more examples, the first connector 164A of the pair of firstfluid connectors 164 is movably connected to the other first connector148A of the pair of second fluid connectors 148 to establish afluid-flow path 190 between the first and second cooling components 136,138. In other words, the fluid bore 164A₁ is movably connected to thefluid piston 148A₁ to establish the fluid-flow path 190 therebetween.For example, the fluid piston 148A₁ is inserted inside the wall 186 ofthe fluid bore 164A₁ such that the O-ring seal 182 is compressed againstthe wall 186. In such examples, the fluid piston 148A₁ and the fluidbore 164A₁ are maintained at a uniform extrusion gap “G₁”circumferentially along the first diameter “D₁” of the fluid bore 164A₁.In some examples, the extrusion gap “G₁” may be around 0.002 inches toabout 0.008 inches.

In some examples, the O-ring seal 182 is compressed against the wall 186of the fluid bore 164A₁, upon movably connecting the fluid piston 148A₁to the fluid bore 164A₁, to prevent leakage of a fluid (as shown inFIGS. 5A, 5B) from the fluid-flow path 190. In some examples, the O-ringseal 182 may be compressed in a range of about 10 percent to 30 percentto maintain the sufficient contact with the wall 186 of the fluid bore164A₁. As discussed herein, the O-ring seal 182 slides along the wall186 of the fluid bore 164A₁ by an up and down movement of the firstcooling component 136 relative to the second cooling component 138. Inother words, the wall 186 slides downwards or upwards, while the O-ringseal 182 maintains the contact with the wall 186, to accommodate thevariation in height (“H₁”, “H₂”) between the first and second electronicchipsets 124, 126. Thus, the O-ring seal 182 may permit the firstcooling component 136 to independently move relative to the secondcooling component 138 to accommodate any variation in height (“H₁”,“H₂”) between the first and second electronic chipsets 124, 126. In someexamples, the variations in height (“H_(i)”, “H₂”) may be around 0.0052inches to about 0.0058 inches.

Referring to FIG. 1D, the O-ring seal 182 may be eccentricallycompressed against the wall 186 of the fluid bore 164A₁ by a tiltingmovement of the first cooling component 136 relative to the secondcooling component 138. In some examples, the O-ring seal 182 may beeccentrically compressed to about 0.15 inches to about 2.5 inches. Insuch examples, the fluid piston 148A₁ and the fluid bore 164A₁ aremaintained at a varied extrusion gap “G₂” circumferentially along thefirst diameter “D₁” of the fluid bore 164A₁. Thus, the O-ring seal 182may permit the first cooling component 136 to independently tiltrelative to the second cooling component 138 to accommodate a variationin flatness (“F₁”, “F₂”) between the first and second electronicchipsets 124, 126. In some examples, the variations in height (“F₁”,“F₂”) may be around 1.975 degrees to about 8.746 degrees. Accordingly,referring to FIGS. 1C-1D, the O-ring seal 182 may permit a 3-dimensionalmovement of the first cooling component 136 relative to the secondcooling component 138 in order to accommodate the variations in at leastone of the height (“H₁”, “H₂”) or the flatness (“F₁”, “F₂”) between thefirst and second electronic chipsets 124, 126.

In some examples, upon mounting of the first cooling component 136 onthe frame 102, the first thermal interfacing surface 160A of the firstcooling component 136 may align with the first thermal interfacingsurface 134A of the first electronic chipset 124. Further, each fastenerof the plurality of first spring loaded fasteners 174 is inserted intothe respective fourth hole 118D in the first cooling component 136 andthe respective second hole 118A in the cover portion 102B to connect thefirst cooling component 136 to the frame 102. In some examples, eachspring of the plurality of first spring loaded fasteners 174 bias thefirst cooling component 136 to move towards the first electronic chipset124, thereby establishing a first thermal interface between the firstthermal interfacing surfaces 160A, 134A of the first cooling component136 and the first electronic chipset 124. In some examples, each of theplurality of second spring loaded fasteners 176 may be accessed (i.e.,for unfastening, for example) via the respective hole of the pluralityof fifth holes 118E in the first cooling component 136. Similarly, eachfastener of the plurality of clamping fasteners may be accessed (i.e.,for unfastening, for example) via the respective hole of the pluralityof fourth clamping holes 114D in the first cooling component 136.Referring to FIGS. 1C-1D, in one or more examples, the O-ring seal 182slides along the wall 186 of the fluid bore 164A₁ by the up and downmovement of the first cooling component 136 relative to the secondcooling component 138, eccentrically compresses against the wall 186 ofthe fluid bore 164A₁, by the tilting movement of the first coolingcomponent 136 relative to the second cooling component 138, or acombination thereof.

FIG. 3 depicts a perspective view of a portion of a second coolingcomponent 138 and a pair of captive fasteners 178 of FIGS. 1A-1B. It maybe noted herein that FIG. 3 does not illustrates a first coolingcomponent 136 for ease of illustration and such an illustration shouldnot be construed as a limitation of the present disclosure. Referring toFIG. 2E, FIG. 2G, and FIG. 3 , each captive fastener of the plurality ofcaptive fasteners 178 is pre-disposed within a respective captivefastener hole of the plurality of captive fastener holes 172. Moreover,each captive fastener of the plurality of captive fasteners 178 isfastened in order to engage each captive fastener 178 with therespective retention tab of the plurality of retention tabs 150 so as tocouple the first and second cooling components 136, 138 to one another.Thus, the captive fasteners 178 may complete the process of assemblingthe cooling module 106 to the electronic circuit module 104.

During operation of the circuit assembly 100, the first and secondelectronic chipsets 124, 126 may generate waste-heat. As will beunderstood, such waste-heat generated by the first and second electronicchipsets 124, 126 is unwanted and may impact operation of the electroniccircuit module 104, if not managed effectively. Accordingly, in someexamples, the proposed cooling module 106 may establish sufficientthermal interfaces between the cooling component and the electronicchips to enable efficient waste-heat transfer from the electronic chipsirrespective of variations in at least one of the height and theflatness between the first and second electronic chipsets 124, 126.Thus, In accordance with the aspects of the present disclosure, thecooling module 106 facilitates effective cooling of the first and secondelectronic chipsets 124, 126 irrespective of variations in at least oneof the height or flatness between the first and second electronicchipsets 124, 126.

FIG. 4 is a flowchart depicting a method 400 of assembling a coolingmodule to an electronic circuit module of a circuit assembly. It shouldbe noted herein that the method 400 is described in conjunction withFIGS. 1A-1D and FIGS. 2A-2G, for example. The method 400 starts at block402 and continues to block 404. At block 404, the method 400 includescoupling the electronic circuit module to a frame of a circuit assembly.In some examples, the electronic circuit module is disposed on a baseportion of the frame. Further, a cover portion of the frame is mountedon the base portion such that the electronic circuit module issandwiched between the base portion and the cover portion. Later, oneclamping fastener of a plurality of clamping fasteners is inserted intoeach clamping hole of a plurality of second, third, and first clampingholes formed respectively in the cover portion of the frame, a circuitboard of the electronic circuit module, and the base portion of theframe, so as to couple the electronic circuit module to the frame. Insome examples, the electronic circuit module includes the circuit board,and a first electronic chipset and a second electronic chipset aredisposed on the circuit board. The method 400 continues to block 406.

At block 406, the method 400 includes connecting a second coolingcomponent of a cooling module in the circuit assembly, to the frame toestablish a second thermal interface between the second coolingcomponent and the second electronic chipset. In some examples, aplurality of second spring loaded fasteners is used to connect thesecond cooling component to the cover portion of the frame. The methodcontinues to block 408.

At block 408, the method 400 includes positioning a first coolingcomponent of the cooling module over the second cooling component toalign a plurality of holes (retention holes) of the first coolingcomponent to a plurality of retention tabs of the second coolingcomponent. The method continues to block 410. At block 410, the method400 includes mounting the first cooling component on the frame. In someexamples, mounting includes positioning the second cooling componentwithin a recess portion of the first cooling component. Further,mounting includes protruding each retention tab of the plurality ofretention tabs along a respective hole of the plurality of retentionholes. Additionally, mounting includes movably connecting each connectorof a pair of first fluid connectors in the first cooling component to arespective connector of a pair of second fluid connectors in the secondcooling component to establish a fluid-flow path between the first andsecond cooling components. In some examples, the method 400 includesperforming additional sub-steps upon mounting the second coolingcomponent on the frame. In some examples, the first sub-step may includetilting the first cooling component relative to the second coolingcomponent to align with a surface of the second cooling component toaccommodate a variation in a flatness between the first electronicchipset and the second electronic chipset. Further, the second sub-stepmay include moving the first cooling component up (and/or down) relativeto the second cooling component, to accommodate a variation in a heightbetween the first electronic chipset and the second electronic chipset.In some examples, mounting of the second cooling component on the framemay cause both a tilting movement, and an up and down movement of thesecond cooling component relative to the first cooling component toaccommodate the variation in the flatness and the height respectively,between the first and second electronic chipsets. In some examples, thecooling module further includes an O-ring seal connected to oneconnector of the pair of first fluid connectors or the pair of secondfluid connectors. In such examples, the O-ring seal slides along a wallof another connector of the pair of first fluid connectors or the pairof second fluid connectors by the up and down movement of the secondcooling component relative to the first cooling component, eccentricallycompresses against the wall by the tilting movement of the secondcooling component relative to the first cooling component, or acombination thereof. The method 400 continues to block 412.

At block 412, the method 400 includes connecting the first coolingcomponent to the frame to establish a first thermal interface betweenthe first cooling component and the first electronic chipset. In someexamples, a plurality of first spring loaded fasteners is used toconnect the first cooling component to the cover portion of the frame.The method 400 may additionally include a step of coupling the first andsecond cooling components to each other by way of inserting each captivefastener of a plurality of captive fastener into a respective captivefastener hole of the plurality of captive fastener holes in the firstcooling component so as to engage each captive fastener to a respectiveretention tab of a plurality of retention tabs of the second coolingcomponent. The method 400 ends at block 414.

FIG. 5A depicts a cross sectional top view of the circuit assembly 100taken along line 2-2′ in FIG. 1B. In particular, FIG. 5A depicts a crosssectional top view of a first cooling component 136 in a cooling module106. FIG. 5B depicts a cross sectional top view of the cooling module106 of FIGS. 1A-1B having a first cooling component 136 and the secondcooling component 138. In particular, FIG. 5B may depict a crosssectional top view of a first cooling portion 160 and a third coolingportion 162 of the first cooling component 136, and a second coolingportion 142 of the second cooling component 138. In the descriptionhereinafter, FIGS. 5A-5B are described concurrently for ease ofillustration.

As discussed hereinabove, the circuit assembly 100 includes a frame 102,an electronic circuit module 104, and the cooling module 106. In suchexamples, the cooling module 106 includes the first cooling component136 (as shown in FIG. 5B) and the second cooling component 138. In someexamples, the first cooling component 136 has a fluid inlet 166, a fluidoutlet 168, a pair of first fluid connectors 164, a first fluid channel192, and a second fluid channel 196. The second cooling component 138has a pair of second fluid connectors 148 and an intermediate fluidchannel 194.

In some examples, the second cooling component 138 is positioned withina recess portion 154 (as shown in FIGS. 2D-2E) of the first coolingcomponent 136 to fluidically couple the first and second coolingcomponents 136, 138 to each other. In such examples, each connector ofthe pair of first fluid connectors 164 is movably connected to arespective connector of the pair of second fluid connectors 148 toestablish a fluid-flow path 190 between the first and second coolingcomponents 136, 138. For example, a first connector 164A of the pair offirst fluid connectors 164 is movably connected to another firstconnector 148A of the pair of second fluid connectors 148 to establishan inlet fluid-flow path 190A between the first and second coolingcomponents 136, 138. Similarly, a second connector 164B of the pair offirst fluid connectors 164 is movably connected to another secondconnector 148B of the pair of second fluid connectors 148 to establishan outlet fluid-flow path 190B between the first and second coolingcomponents 136, 138. Accordingly, the pair of first and second fluidconnectors 164, 148 enable the first cooling component 136 to befluidically connected to the second cooling component 138. In someexamples, each connector of the pair of first fluid connectors 164 isone of a fluid piston or a fluid bore. Further, each connector of thepair of second fluid connectors 148 is the other one of the fluid pistonor the fluid bore. In the examples of FIGS. 1C-1D and FIGS. 5A-5B, eachconnector of the pair of first fluid connectors 164 is the fluid bore164A₁ (see, FIGS. 1C-1D) and each connector of the pair of second fluidconnectors 148 is the fluid piston 148A₁ (see, FIGS. 1C-1D), forexample. The cooling module 106 further includes an O-ring seal 182 (asshown in FIGS. 1C-1D). In such examples, the O-ring seal 182 is disposedin an outer circumferential groove 180 (as shown in FIGS. 1C-1D) of thefluid piston 148A₁. The O-ring seal 182 is compressed against a wall 186of the fluid bore 164A₁, upon movably connecting the fluid piston 148A₁to the fluid bore 164A₁, so as to prevent leakage of a fluid from theinlet fluid-flow path 190A and the outlet fluid-flow path 190B. Further,as discussed hereinabove, the O-ring seal 182 may slide along the wall186 of the fluid bore 164A₁ (or the wall 186 may slide along the O-ringseal 182), by an up and down movement of the second cooling component138 relative to the first cooling component 136 so as to accommodate thevariation in height between a first electronic chipset 124 and a secondelectronic chipset 126. Similarly, the O-ring seal 182 is eccentricallycompressed against the wall 186 of the fluid bore 164A₁ by a tiltingmovement of the first cooling component 136 relative to the secondcooling component 138 so as to accommodate the variation in flatnessbetween the first electronic chipset 124 and the second electronicchipset 126.

In some examples, each channel of the first fluid channel 192 and thesecond fluid channel 196 is formed within the first cooling component136. In particular, the first fluid channel 192 is formed within thefirst and third cooling portions 160, 162 respectively (as labeled inFIGS. 2D-2E), of the first cooling component 136. The second fluidchannel 196 is formed within the third cooling portion 162. Similarly,the intermediate fluid channel 194 is formed within the second coolingcomponent 138. In particular, the intermediate fluid channel 194 isformed within the second cooling portion 142 (as labeled in FIG. 2D) ofthe second cooling component 138. In some examples, the first fluidchannel 192 extends between the fluid inlet 166 and the first connector164A of the pair of first fluid connectors 164. The second fluid channel196 extends between the second connector 164B of the pair of first fluidconnectors 164 and the fluid outlet 168. Further, the intermediate fluidchannel 194 extends between the first connector 148A and the secondconnector 148B of the pair of second fluid connectors 148.

In one or more examples, the first fluid channel 192 includes a supplysection 192A, a body section 192B, and a return section 192C. In someexamples, the body section 192B has a tortuous or a circuitous flowroute. For example, the body section 192B is bifurcated into a firstbody section 192B₁, and a second body section 192B₂. Further, the firstbody section 192B₁ and the second body section 192B₂ are merged into athird body section 192B₃. In some examples, the first body section 192B₁and the second body section 192B₂ are parallel sections. In someexamples, the intermediate fluid channel 194 has a single-pass flowroute. In some examples, the body section 192B and the intermediatefluid channel 194 include micro-channels. In some examples, eachmicro-channel may have a width of about 0.15 millimeter.

Referring to FIG. 5A, the fluid inlet 166 and the fluid outlet 168 aredisposed spaced apart from each other, and formed in a first peripheralwall 162A (see, FIG. 2D) of the third cooling portion 162. Further, thefirst fluid channel 192 is formed in the third cooling portion 162 andthe first cooling portion 160. For example, the supply section 192A isformed in the third cooling portion 162, the body section 192B is formedin the first cooling portion 160, and the return section 192C is formedin the first and third cooling portions 160, 162. In such examples, apair of connector body channels 192D connects the first and second bodysections 192B,, 192B₂ respectively to the supply section 192A. In someexamples, each of the pair of connector body channels 192D is a radialchannel, which extends between the third and first cooling portions 162,160 respectively. Further, the return section 192C is an inclinedsection, which extends between the first and third cooling portions 160,162 respectively. Further, the intermediate fluid channel 194 is formedin the second cooling portion 142. Similarly, the second fluid channel196 is formed in the third cooling portion 162.

Referring to FIG. 5B, the first body section 192B₁, and the second bodysection 192B₂ extends over the plurality of first electronic chips 124Aof a first electronic chipset 124. The third body section 1928 ₃ extendsover the second electronic chip 124B of the first electronic chipset124. The intermediate fluid channel 194 extends over the thirdelectronic chip 126A of a second electronic chipset 126 disposed on thecircuit board 128.

During operation of the circuit assembly 100, the first and secondelectronic chipsets 124, 126 may generate waste-heat. As will beunderstood, such waste-heat generated by the first and second electronicchipsets 124, 126 are unwanted and may impact operation of theelectronic circuit module 104, if not managed effectively. Accordingly,in some examples, the proposed cooling module 106 may establishsufficient thermal interfaces between the cooling component and theelectronic chips to enable efficient waste-heat transfer from theelectronic chips irrespective of variations in at least one of theheight and the flatness between the first and second electronic chipsets124, 126. Further, in some examples, the proposed cooling module 106 mayinclude the fluid channel having the tortuous flow route in order toincrease a) velocity of the fluid within the fluid channel and b) heattransfer co-efficient between the cooling component and the fluid.Therefore, the proposed cooling module 106 may receive the fluid at areduced volumetric flow rate, thereby allowing the CDU to accommodatethe cool fluid (secondary fluid) requirement of multiple compute nodes(or multiple circuit assemblies 100) in each server system of thedatacenter environment. In some examples, the volumetric flow rate maybe around 0.12 gallons per minute.

Referring to FIG. 5B, the first cooling component 136 receives a coolfluid 198A via the fluid inlet 166. For example, the first fluid channel192 of the first cooling component 136 receives the cool fluid 198A fromthe CDU, for example. In such examples, the supply section 192A of thefirst fluid channel 192 directs the cool fluid 198A to the body section192B. In the body section 192B, the cool fluid 198A absorbs thewaste-heat from the first electronic chipset 124, and generates apartially hot fluid 198B. For example, the cool fluid 198A is bifurcatedinto a first portion 198A₁ and a second portion 198A₂ in the bodysection 192B. The first portion 198A₁ is directed to the first bodysection 192B₁ to absorb the waste-heat from the plurality of firstelectronic chips 124A arranged in the first row 127A (as shown in FIG.2B) and generate a first portion of the partially hot fluid 198B₁.Similarly, the second portion 198A₂ is directed to the second bodysection 192B₂ to absorb the waste-heat from the plurality of firstelectronic chips 124A arranged in the second row 127B (as shown in FIG.2B) and generate a second portion of the partially hot fluid 198B₂. Thefirst and second portions of the partially hot fluid 198B₁, 198B₂ arelater mixed together to form a mixed portion of the partially hot fluid198B₃ in the third body section 192B₃. The mixed portion of thepartially hot fluid 198B₃ is directed in the third body section 1928 ₃to absorb the waste-heat from the second electronic chip 124B andgenerate the partially hot fluid 198B. Further, the third body section1928 ₃ directs the partially hot fluid 198B to the return section 192C.In such examples, the return section 192C discharges the partially hotfluid 198B into the intermediate fluid channel 194 of the second coolingcomponent 138 via the inlet fluid-flow path 190A. In some examples, theintermediate fluid channel 194 directs the partially hot fluid 198B fromone end portion 184 (as shown in FIG. 1C) to another end portion (notlabeled) to absorb the waste-heat from the third electronic chip 126A ofthe second electronic chipset 126 and generate a hot fluid 198C.Further, the intermediate fluid channel 194 discharges the hot fluid198C from the other end portion to the second fluid channel 196 of thefirst cooling component 136 via the outlet fluid-flow path 190B. In someexamples, the second fluid channel 196 further directs the hot fluid198C to the fluid outlet 168 so as to return the hot fluid 198C from thefirst cooling component 136.

As discussed herein, the first fluid channel 192 of the first coolingcomponent 136, having the tortuous flow route may significantly increasea velocity of the fluid (e.g., the cool fluid 198A, and the partiallyhot fluid 198B) within the first cooling component 136 to efficientlydissipate the waste-heat from the first electronic chipset 124. Thus,the first fluid channel 192 may decrease the volumetric flow rate of thefluid (e.g., the cool fluid 198A) to be circulated in the cooling module106 for cooling the first electronic chipset 124. For example, the bodysection 192B of the first fluid channel 192 having the bifurcated fluidsections (i.e., the first body section 192B₁, and the second bodysection 192B₂) may enable the cool fluid 198A to be directed in parallelat a relatively high velocity so as to uniformly cool the plurality offirst electronic chips 124A (memory chips). In one or more examples, thebifurcation of the body section 192B into the first body section 192B₂,and the second body section 192B₂ may reduce a flow area for the flow ofthe fluid, thereby increasing i) the velocity of the cool fluid 198A inthe bifurcated body sections 192B₁, 192B₂ and ii) the heat transferco-efficient between the cool fluid 198A and the plurality of firstelectronic chips 124A. Further, the merged body section (i.e., the thirdbody section 192B₃) may enable the mixed portion of the partially hotfluid 198B₁, 198B₂ to be directed at the relatively high velocity so asto effectively cool the high powered second electronic chip 124B (or GPUchip). In one or more examples, the merging of the first body section192B₁, and the second body section 192B₂ into the merged body section1928 ₃ may mix the flow of the first and second partially hot fluidportions 198B₁, 198B₂ into the mixed portion of the partially hot fluid198B₃, thereby increasing i) the velocity of the mixed portion of thepartially hot fluid 198B₁, 198B₂ and ii) the heat transfer co-efficientbetween the mixed portion of the partially hot fluid 198B₁, 198B₂ andthe second electronic chip 124B. Further, as discussed herein, theintermediate fluid channel 194 of the first cooling component 136,having a single-pass flow route may enable the partially hot fluid 198Bto be directed at a relatively low velocity so as to effectively coolthe low powered third electronic chip 126A (or CPU chip). In one or moreexamples, the third electronic chip 126A is a low powered electronicchipset, and thus generates a substantially low waste-heat in comparisonwith the waste-heat generated by a high powered electronic chipset, suchas the plurality of first electronic chips 124A and the secondelectronic chip 124B. Additionally, the third electronic chip 126A has acase temperature, which is higher than the case temperature of theplurality of first electronic chips 124A and the second electronic chip124B. It may be noted herein that the term “case temperature” may referto a maximum temperature that the electronic chip may attain whileoperating to execute the assigned task or workload. Accordingly, thesecond cooling component 138 may not be required to have the tortuousflow route to dissipate the waste-heat from the third electronic chip126A, which has a low case temperature and low power consumption.

In one or more examples, the flow of the fluid (e.g., the cool fluid198A, and the partially hot fluid 198B) in the tortuous flow route ofthe first fluid channel 192 may cause a relatively high pressure drop ofthe fluid in the first cooling component 136. Similarly, the flow of thefluid (e.g., the partially hot fluid 198B) in the single-pass flow routeof the intermediate fluid channel 194 may also cause the pressure dropof the fluid in the second cooling component 138. Accordingly, thecooling module 106 having the relatively high pressure drop of the fluidmay be advantageous to the CDU in order to maintain a balanced flow ofthe fluid across multiple circuit assemblies 100 (or compute nodes) ineach electronic system (or each server system) of the datacenterenvironment. In some examples, the first fluid channel 192 having thetortuous flow route may enable the cooling module 106 to have thevolumetric flow rate of about 0.12 gallons per minutes. Accordingly, theCDU in the datacenter environment may be enabled to accommodate the coolfluid 198A requirement of multiple server systems of the datacenterenvironment. In some examples, the CDU may be provisioned to supply thecool fluid 198A for multiple racks, for example, to at least four racks,where each rack may have about thirty-two server systems, and eachserver system may have about eight circuit assemblies, and each circuitassembly may have at least one cooling module.

In some examples, the plurality of first electronic chips 124A may havea first case temperature (e.g., a low case temperature), and the secondelectronic chip 124B may have a second case temperature (e.g., a highcase temperature), where the second case temperature is greater than thefirst case temperature. In such examples, since the cool fluid 198A isfirst directed to the bifurcated body sections 192B₁, 192B₂, which arein thermal contact with the plurality of first electronic chips 124Ahaving the low case temperature, the cool fluid 198A may have asufficient thermal margin to efficiently dissipate the waste-heat fromthe plurality of first electronic chips 124A. As used herein, the term“thermal margin” may refer to a temperature difference between the casetemperature of the electronic chip and the temperature of the fluid.Further, since the mixed portion of the partially hot fluid 198B₁, 198B₂is directed to the merged body section 192B₂, which is in thermalcontact with the second electronic chip 124B having the high casetemperature, the mixed portion of the partially hot fluid 198B₁, 198B₂may still have the sufficient thermal margin to efficiently dissipatethe waste-heat from the second electronic chip 124B. In some examples,the third electronic chip 126A may have a third case temperature (e.g.,a highest case temperature), which is greater than the first and secondcase temperature of the plurality of first electronic chips 124A and thesecond electronic chip 124B respectively. In such examples, since thepartially hot fluid 198B is directed to the intermediate fluid channel194, which is in thermal contact with the third electronic chip 126Ahaving the highest case temperature, the partially hot fluid 198B maystill have the sufficient thermal margin to efficiently dissipate thewaste-heat from the third electronic chip 126A.

FIG. 6 is a flowchart depicting a method 600 of dissipating a waste-heatfrom an electronic circuit module of a circuit assembly. It should benoted herein that the method 600 is described in conjunction with FIGS.1A-1D and FIGS. 5A-5B, for example. The method 600 starts at block 602and continues to block 604. At block 604, the method 600 includesreceiving a cool fluid by a first cooling component of a cooling modulevia a fluid inlet in the first cooling component. In some examples, thefirst cooling component is connected to a frame of the electroniccircuit assembly, to establish a first thermal interface with a firstelectronic chipset of the electronic circuit module coupled to theframe. In some examples, a plurality of first spring loaded fasteners isused to connect the first cooling component to the frame. The method 600continues to block 606.

At block 606, the method 600 includes directing the cool fluid in afirst fluid channel of the second cooling component, to absorb awaste-heat from the first electronic chipset, and generate a partiallyhot fluid. In one or more examples, the first fluid channel includes asupply section, a body section, and a return section. The body sectionis bifurcated into a first body section, and a second body section.Further, the first body section and the second body section are mergedinto a third body section. In some examples, the first body section andthe second body section are parallel sections. In some examples,directing the cool fluid in the first fluid channel includes a pluralityof sub-steps. In some examples, a first sub-step includes directing afirst portion of the cool fluid in the first body section to generatethe first portion of the partially hot fluid. In some examples, thefirst portion of the cool fluid absorbs the waste-heat from theplurality of first electronic chips of a first electronic chipset,arranged along a first row, and generates the first portion of thepartially hot fluid. A second sub-step includes directing a secondportion of the cool fluid in the second body section to generate thesecond portion of the partially hot fluid. In some examples, the firstportion of the cool fluid absorbs the waste-heat from the plurality offirst electronic chips of the first electronic chipset, arranged along asecond row, and generates the second portion of the partially hot fluid.In one or more examples, the first and second portions of the cool fluidare directed in parallel to each other. In some examples, eachelectronic chip of the plurality of first electronic chips may include amemory chip. A third sub-step includes directing a mixed portion of thepartially hot fluid in the third body section to absorb the waste-heatfrom the second electronic chip of the first electronic chipset, andgenerate the partially hot fluid, where the mixed portion of thepartially hot fluid is a mixture of the first and second portions of thepartially hot fluid. In some examples, the second electronic chip mayinclude a graphics processing unit (GPU) chip. The method continues toblock 608.

As discussed hereinabove, in some examples, the plurality of firstelectronic chips has a first case temperature “T₁”, and the secondelectronic chip has a second case temperature “T₂”. It may be notedherein that the term “case temperature” may refer to maximum temperaturethat the electronic chip may attain while operating to execute theassigned task or workload. In some examples, the second case temperature“T₂” is greater than the first case temperature “T₁”. Since the firstcase temperature “T₁” is smaller than the second case temperature “T₂”,the first fluid channel 192 is designed such that the cool fluid isfirst directed into the first body section and second body section ofthe body section, to absorb the waste-heat from the plurality of firstelectronic chips, and then the partially hot fluid is directed in thethird body section of the body section, to absorb the waste-heat fromthe second electronic chip. In some examples, the body section is firstbifurcated into two channels, for examples, the first body section andthe second body section in order to i) direct the cool fluidsimultaneously to the plurality of first electronic chips arranged alongtwo parallel rows, and ii) increase velocity of the cool fluid toimprove a cooling efficiency over the plurality of first electronicchips (i.e., memory chips). In some examples, the velocity of the coolfluid may be increased due to decease in flow area by the bifurcation ofthe first fluid channel. Later, the first body and second body sectionsare joined or merged together to form the third body section so as toincrease the velocity of the partially hot fluid to further improve thecooling efficiency over the second electronic chip (i.e., high power GPUchip).

At block 608, the method 600 includes discharging the partially hotfluid from the first fluid channel into an intermediate fluid channel ofa second cooling component of the cooling module, via an inletfluid-flow path established between the first and second coolingcomponents. In some examples, the second cooling component is positionedwithin a recess portion of the first cooling component, and connected tothe frame to establish a second thermal interface with a secondelectronic chipset of the electronic circuit module. The methodcontinues to block 610. At block 610, the method 600 includes directingthe partially hot fluid in the intermediate fluid channel to absorb thewaste-heat from the second electronic chipset, and generate a hot fluid.The second electronic chipset may include the third electronic chip,such as a central processing unit (CPU) chip. In some examples, thethird electronic chip has a third case temperature “T₃”. In someexamples, the third case temperature “T₃” is greater than the secondcase temperature “T₂” and the third case temperature “T₃”. Since thethird case temperature “T₃” is greater than the second case temperature“T₂” and the third case temperature “T₃”, the first fluid channel isdesigned such that the partially hot fluid is directed into theintermediate fluid channel from the first fluid channel so as toeffectively absorb the waste-heat from the third electronic chip andgenerate the hot fluid. In one or more examples, the intermediate fluidchannel has a single-pass flow route, as the partially hot fluid has toonly dissipate the waste-heat from the third electronic chip. The methodcontinues to block 612. At block 612, the method 600 includesdischarging the hot fluid from the intermediate fluid channel into asecond fluid channel of the first cooling component via an outletfluid-flow path established between the first and second coolingcomponents. The method 600 continues to block 614. At block 614, themethod 600 includes directing the hot fluid in the second fluid channelto the fluid outlet to return the hot fluid from the first coolingcomponent. The method 600 ends at block 616.

FIG. 7 is a cross sectional view of a first connector 764A of a pair offirst fluid connectors 764 movably connected to another first connector748A of a pair of second fluid connectors 748 according to anotherexample implementation of the present disclosure. In some examples, thefirst connector 764A is a fluid piston 764A₁. In such examples, thefluid piston 764A₁ has a first diameter “D₁”, and an outercircumferential groove 780 formed on a portion of the fluid piston 764A₁has a second diameter “D₂”. In some examples, the first diameter “D₁” isgreater than the second diameter “D₂”. In some examples, a coolingmodule further includes an O-ring seal 782 disposed in the outercircumferential groove 780 of the fluid piston 764A₁. In some examples,the other first connector 748A is a fluid bore 748A₁. In such examples,the fluid bore 748A₁ has a wall 786 (or circumferential wall) having asecond diameter “D₃”. In some examples, the third diameter “D₃” isgreater than the first diameter “D₁”.

In one or more examples, the first connector 764A of the pair of firstfluid connectors 764A is movably connected to the other first connector748A of the pair of second fluid connectors 748 to establish afluid-flow path 790 between a second cooling component and a firstcooling component respectively, of the cooling module. In other words,the fluid piston 764A₁ is movably connected to the fluid bore 748A₁ toestablish the fluid-flow path 790 therebetween, for example, an inletfluid-flow path 790A. For example, the fluid piston 764A₁ is insertedinside the wall 786 of the fluid bore 748A₁ such that the O-ring seal782 is compressed against the wall 786 of the fluid bore 748A₁. In someexamples, the O-ring seal 782 is compressed against the wall 786 of thefluid bore 748A₁, upon movably connecting the fluid piston 764A₁ to thefluid bore 748A₁, to prevent leakage of a fluid from the fluid-flow path790.

In accordance to the present implementation, the proposed cooling modulemay establish a sufficient thermal interface between the coolingcomponents and the electronic chips to enable efficient heat transferfrom the electronic chips irrespective of variations in the height andthe flatness between the electronic chips. Further, since each connectorof the pair of the first fluid connectors or each connector of the pairof second fluid connectors has the O-ring seal, the first coolingcomponent may be permitted to independently move relative to the secondcooling component. In other words, the O-ring seal may permit a3-dimensional movement of the first cooling component relative to thesecond cooling component in order to accommodate the variations in atleast one of the height or the flatness between the first and secondelectronic chips. The cooling module may be construed as a monolithiccooling module due to the floatable (movable) design of the firstcooling component disposed on the second cooling component, which mayminimize cracking of electronic chips at the time of installation and/orduring shipping/handling, and in the field. Further, the floatingcapability of the first cooling component may help to accommodatevariations in height and co-planarity (flatness) tolerances between twoadjacent electronic chips minimizing raised areas or indentations.Additionally, since the spring loaded fasteners are used to connect thecooling component to the frame, the cooling module may provide improvedfactory installation, and an improved field and factory servicingexperience. The usage of the captive fasteners (or set screws) to lockthe floating of the second cooling component in place after it ispositioned on the respective electronic chips, may ensure thatelectronic chips are not damaged due to fluid pressure force, duringassembly, shipping, servicing, or the like.

Further, as discussed herein, the design of the first fluid channel inthe first cooling component may significantly increase a velocity of afluid, thereby increasing a cooling efficiency of a high poweredelectronic chipset, and reducing a volumetric flow rate of the fluiddirected within the cooling module. In otherwords, the first fluidchannel having the circuitous or the tortuous flow route may enable thefluid to be directed within the first cooling component at a highvelocity for a low volumetric flow rate, thereby assist in efficientdissipation of the waste-heat from the first electronic chipset.Additionally, the design of the intermediate flow channel in the secondcooling component may decrease the velocity of the fluid, therebyincreasing the cooling efficiency of a low powered electronic chipset,and reducing the volumetric flow rate of the fluid directed within thecooling module, thereby assist in efficient dissipation of thewaste-heat from the second electronic chipset. Accordingly, the fluidchannels in the first and second cooling components may enable thecooling module to have the volumetric flow rate of about 0.12 gallonsper minutes. Accordingly, a thermal management unit of the datacenterenvironment, having a coolant distribution unit (CDU) to distribute thecoolant fluid, may be provisioned to supply the cool fluid to at leastfour racks, each rack having about thirty-two server systems, and eachserver system having about eight circuit assemblies, and each circuitassembly having at least one cooling module. Additionally, variousfeatures as illustrated in the examples described herein may beimplemented as a tool-less method of quickly and easily assembling/disassembling a cooling module to an electronic circuit module by atechnician or a customer, thus, reducing the down time of the serversystem and efforts associated to such events of assembling anddisassembling the cooling module to the electronic circuit module of theserver system.

In the foregoing description, numerous details are set forth to providean understanding of the subject matter disclosed herein. However,implementation may be practiced without some or all of these details.Other implementations may include modifications, combinations, andvariations from the details discussed above. It is intended that thefollowing claims cover such modifications and variations.

What is claimed is:
 1. A cooling module for an electronic circuitmodule, comprising: a first cooling component comprising a first fluidchannel and a second fluid channel, wherein the first fluid channelcomprises a supply section, a return section, and a body section; and asecond cooling component comprising an intermediate fluid channel,wherein the second cooling component is positioned within a recessportion of the first cooling component and is fluidically connected tothe first cooling component, wherein the body section is bifurcated intoa first body section and a second body section, wherein the first andsecond body sections are further merged into a third body section,wherein the supply section is connected to the first and second bodysections, wherein the return section is connected to the third bodysection, and the intermediate fluid channel via an inlet fluid-flow pathestablished between the first and second cooling components, wherein thesecond fluid channel is connected to the intermediate fluid channel viaan outlet fluid-flow path established between the first and secondcooling components.
 2. The cooling module of claim 1, wherein the bodysection comprises micro-channels formed within the first coolingcomponent, and wherein the intermediate fluid channel comprises themicro-channels formed within the second cooling component.
 3. Thecooling module of claim 1, wherein the first cooling component furthercomprises a pair of first fluid connectors, and wherein the secondcooling component comprises a pair of second fluid connectors.
 4. Thecooling module of claim 3, wherein a first connector of the pair offirst fluid connectors is movably connected to another first connectorof the pair of second fluid connectors to establish the inlet fluid-flowpath between the first and second cooling components.
 5. The coolingmodule of claim 3, wherein a second connector of the pair of first fluidconnectors is movably connected to another second connector of the pairof second fluid connectors to establish the outlet fluid-flow pathbetween the first and second cooling components.
 6. The cooling moduleof claim 3, wherein the first cooling component further comprises afluid inlet and a fluid outlet, wherein the first fluid channel extendsbetween the fluid inlet and a first connector of the pair of first fluidconnectors, and wherein the second fluid channel extends between asecond connector of the pair of first fluid connectors and the fluidoutlet.
 7. The cooling module of claim 6, wherein the intermediate fluidchannel extends between the first connector and the second connector ofthe pair of second fluid connectors.
 8. The cooling module of claim 3,wherein each connector of the pair of first fluid connectors is one of afluid piston or a fluid bore, and wherein each connector of the pair ofsecond fluid connectors is the other one of the fluid piston or thefluid bore.
 9. The cooling module of claim 8, further comprising anO-ring seal, wherein the O-ring seal is disposed in an outercircumferential groove of the fluid piston, and wherein the O-ring sealis compressed against a wall of the fluid bore, upon movably connectingthe fluid piston to the fluid bore, to prevent leakage of fluid from theinlet fluid-flow path and the outlet fluid-flow path.
 10. The coolingmodule of claim 9, wherein the O-ring seal slides along the wall of thefluid bore by an up and down movement of the second cooling componentrelative to the first cooling component, eccentrically compressesagainst the wall of the fluid bore by a tilting movement of the secondcooling component relative to the first cooling component, or acombination thereof.
 11. A method of cooling an electronic circuitmodule of an electronic circuit assembly, the method comprising:receiving a cool fluid by a first cooling component of a cooling module,wherein the first cooling component is connected to a frame of theelectronic circuit assembly, to establish a first thermal interface witha first chipset of the electronic circuit module coupled to the frame;directing the cool fluid in a first fluid channel of the first coolingcomponent, to absorb a waste-heat from the first chipset, and generate apartially hot fluid; discharging the partially hot fluid from the firstfluid channel into an intermediate fluid channel of a second coolingcomponent of the cooling module, via an inlet fluid-flow pathestablished between the first and second cooling components, wherein thesecond cooling component is positioned within a recess portion of thefirst cooling component and is fluidically connected to the firstcooling component, and wherein the second cooling component is connectedto the frame to establish a second thermal interface with a secondchipset of the electronic circuit module; directing the partially hotfluid in the intermediate fluid channel to absorb the waste-heat fromthe second chipset, and generate a hot fluid; discharging the hot fluidfrom the intermediate fluid channel into a second fluid channel of thefirst cooling component via an outlet fluid-flow path establishedbetween the first and second cooling components; and directing the hotfluid in the second fluid channel to return from the first coolingcomponent.
 12. The method of claim 11, wherein the first chipset and thesecond chipset are disposed on a circuit board of the electronic circuitmodule, wherein the first chipset comprises a plurality of firstelectronic chips and a second electronic chip, and wherein the pluralityof first electronic chips is arranged along a first row and a second rowlocated around the second electronic chip.
 13. The method of claim 12,wherein the first fluid channel comprises a supply section, a returnsection, and a body section, wherein the body section is bifurcated intoa first body section and a second body section, wherein the first andsecond body sections are further merged into a third body section,wherein the supply section is connected to the first and second bodysections, and wherein the return section is connected to the third bodysection.
 14. The method of claim 13, wherein the first body sectionextends over the plurality of first electronic chips arranged along thefirst row, wherein the second body section extends over the plurality offirst electronic chips arranged along the second row, and wherein thethird body section extends over the second electronic chip.
 15. Themethod of claim 14, wherein directing the cool fluid in the first fluidchannel comprises: directing a first portion of the cool fluid in thefirst body section to generate the first portion of the partially hotfluid; directing a second portion of the cool fluid in the second bodysection to generate the second portion of the partially hot fluid,wherein the first and second portions of the cool fluid are directed inparallel to each other; and directing a mixed portion of the partiallyhot fluid in the third body section to generate the partially hot fluid,wherein the mixed portion of the partially hot fluid is a mixture of thefirst and second portions of the partially hot fluid.
 16. The method ofclaim 13, wherein the intermediate fluid channel extends over the secondchipset.
 17. The method of claim 13, wherein the first cooling componentcomprises a pair of first fluid connectors, wherein the second coolingcomponent comprises a pair of second fluid connectors, wherein a firstconnector of the pair of first fluid connectors is movably connected toanother first connector of the pair of second fluid connectors toestablish the inlet fluid-flow path between the first and second coolingcomponents, and wherein a second connector of the pair of first fluidconnectors is movably connected to another second connector of the pairof second fluid connectors to establish the outlet fluid-flow pathbetween the first and second cooling components.
 18. The method of claim17, wherein each connector of the pair of first fluid connectors is oneof a fluid piston or a fluid bore, wherein each connector of the pair ofsecond fluid connectors is the other one of the fluid piston or thefluid bore, wherein an O-ring seal is disposed in an outercircumferential groove of the fluid piston, wherein the O-ring seal iscompressed against a wall of the fluid bore, upon movably connecting thefluid piston to the fluid bore, to prevent leakage of i) the partiallyhot fluid from the inlet fluid-flow path and ii) the hot fluid from theoutlet fluid-flow path.
 19. The method of claim 17, wherein the bodysection comprises micro-channels formed within the first coolingcomponent, wherein the first fluid channel extends between a fluid inletof the first cooling component, and the first connector of the pair offirst fluid connectors, and wherein the second fluid channel extendsbetween the second connector of the pair of first fluid connectors and afluid outlet of the first cooling component.
 20. The method of claim 17,wherein the intermediate fluid channel comprises micro-channels formedwithin the second cooling component, and wherein the intermediate fluidchannel extends between the first connector and the second connector ofthe pair of second fluid connectors.